Made an account just to post this. Had a user with the same problem in Google Workspace. Despite marking email as "not spam", they kept getting their email moved into junk mail for no apparent reason. we also tried marking the sender as trusted in account settings in their google workspace account. The solution was to block access from Samsung Email Client on the Google Side (revoke the OAuth token). Suddenly the email was not sent to spam again. I got the hunch from here: https://support.google.com/mail/thread/121024512?hl=en-GB
